BACKGROUND: Associations between adolescent health-related quality of life (HRQoL), bullying, and aggression are not well understood. We used baseline data from a large-cluster randomized school trial to study the relationship between HRQoL, bullying experience, and other demographic factors. METHODS: Cross-sectional self-reported questionnaires collected pre-randomization from the on-going INCLUSIVE trial. The questionnaires were completed in the classroom. The Gatehouse Bullying Scale measured bullying victimization and the Edinburgh Study of Youth Transitions and Crime school misbehavior subscale (ESYTC) measured aggressive behaviors. HRQoL was assessed using the Child Health Utility 9 Dimensions (CHU-9D) and general quality of life using the Pediatric Quality of Life Inventory (PedsQL). Participants were a cohort of year 7 students (age 11-12 years) from 40 state secondary schools in England. Descriptive statistics for the CHU-9D and PedsQL were calculated using standard methods with tests for differences in median scores by sex assessed using quantile regression. Correlation between HRQoL measures was conducted using Spearman's rank correlation coefficients. Predictors of HRQoL were identified using univariate and multiple regressions. RESULTS: A total of 6667 students filled out the questionnaire. The CHU-9D was correlated with the PedsQL (0.63, p < 0.001). The multivariable regression results suggest that if students were bullied frequently and upset it resulted in a decrement in CHU-9D scores of (-0.108) and fall in PedsQL score of (-16.2). The impact of the antisocial/aggressive behavior on the ESYTC scale resulted in a utility decrement of -0.004 and fall of -.5 on the PedsQL. CONCLUSIONS: Adolescents' involvement in bullying and aggression is a strong correlate of HRQoL. These data have important implications for the potential cost-effectiveness of reducing bullying and aggression in schools.